KEY POINTS:
Three-times golf major champion Phil Mickelson has hired swing coach Butch Harmon in a bid to improve the accuracy of his long game.
Mickelson, who blew a golden opportunity to win last year's US Open at Winged Foot with a wayward tee shot at the last, had previously worked with Rick Smith for most of his career.
However, the American left-hander plans to retain his close personal and professional ties with Smith.